condition mean min max ZT0-3 4.163408333333333 3.756845 4.9485399999999995 ZT4-7 2.625675 2.625675 2.625675 ZT8-11 2.48201 2.48201 2.48201 ZT12-15 4.1269075 3.084245 5.16957 ZT16-19 2.087315 2.087315 2.087315 ZT20-23 2.95918 2.95918 2.95918